TPS70345, TPS70348, TPS70351, TPS70358, TPS70302

DUAL-OUTPUT LOW-DROPOUT VOLTAGE REGULATORS

WITH POWER UP SEQUENCING FOR SPLIT VOLTAGE DSP SYSTEMS

SLVS285A – AUGUST 2000 – REVISED OCTOBER 2002

2

POST OFFICE BOX 655303

description (continued)

The TPS703xx family of voltage regulators offers very low dropout voltage and dual outputs with power up

sequence control, which is designed primarily for DSP applications. These devices have low noise output

performance without using any added filter bypass capacitors and are designed to have a fast transient

response and be stable with 47

µF low ESR capacitors.

These devices have fixed 3.3-V/2.5-V, 3.3-V/1.8-V, 3.3-V/1.5-V, 3.3-V/1.2-V, and adjustable voltage options.

Regulator 1 can support up to 1 A, and regulator 2 can support up to 2 A. Separate voltage inputs allow the

designer to configure the source power.

Because the PMOS pass element behaves as a low-value resistor, the dropout voltage is very low (typically 160

mV on regulator 1) and is directly proportional to the output current. Additionally, since the PMOS pass element

is a voltage-driven device, the quiescent current is very low and independent of output loading (maximum of

250

µA over the full range of output current). This LDO family also features a sleep mode; applying a high signal

to EN (enable) shuts down both regulators, reducing the input current to 1

The device is enabled when the EN pin is connected to a low-level input voltage. The output voltages of the two

The input signal at the SEQ pin controls the power-up sequence of the two regulators. When the device is

current source.

For each regulator, there is an internal discharge transistor to discharge the output capacitor when the regulator

is turned off (disabled).

reset) for the circuitry supplied by regulator 1.

The TPS703xx features a RESET (SVS, POR, or power on reset). RESET is an active low, open drain output

and requires a pullup resistor for normal operation. When pulled up, RESET goes to a high impedance state

connected to MR1 or MR2. RESET can be used to drive power on reset or a low-battery indicator. If RESET

is not used, it can be left floating.

undervoltage lockout circuit that prevents each output from turning on until the respective input reaches 2.5 V.

AVAILABLE OPTIONS

TJ

REGULATOR 1

VO (V)

REGULATOR 2

VO (V)

TSSOP

(PWP)

3.3 V

1.2 V

TPS70345PWP

3.3 V

1.5 V

TPS70348PWP

– 40

°Cto125°C

3.3 V

1.8 V

TPS70351PWP

– 40

°C to 125°C

3.3 V

2.5 V

TPS70358PWP

Adjustable

(1.22 V to 5.5 V)

Adjustable

(1.22 V to 5.5 V)

TPS70302PWP

NOTE: The TPS70302 is programmable using external resistor dividers (see

application information) The PWP package is available taped and reeled. Add

an R suffix to the device type (e.g., TPS70302PWPR).